In consideration of the working characteristics of a Charge Coupled Devices(CCD)， an imaging detector based on CCD and CsI scintillator was presented by using flexible exposure control and multi-frame superpositioning techniques to improve the detection efficiency of hard X-ray. An experimental platform was built， in which a nickel collimator based on a micromachining techniques was adopted as the imaging spatial target. In the experiment， the 55Fe X-ray source was adopted for direct imaging of CCD itself. Then， the 241Am X-ray source was used for both direct imaging by CCD itself and indirect imaging by the hard X-ray imaging detector. Finally， some phenomenon exhibited in the images such as drag shadows， clarity gradients， and different area brightness were analyzed. The results indicate that the techniques presented not only expands the responsive energy range， but also improves the quantum efficiency significantly as comparing with CCD itself. In addition， under exposure with 241Am X-ray sources， hard X-ray imaging with a spatial resolution better than 50 μm was achieved. The imaging detector is promising to be a position sensitive detector for future space astronomical observations.